Large RV-Towing Truck Issues

Now that you have decided on a towable recreational vehicle, take time to research the tow vehicle requirements before finalizing your trailer decision. This is a crucial step because large trucks required for the safe towing of heavy trailers introduce potential issues which car and light truck operators may not be aware of.

In this article I will offer suggestions for overcoming some of these issues and prepare you for the inevitability of others. For the purposes of this article, I define a large truck as one of the following: full size pickup with a long wheelbase, truck with dual rear wheels, and all medium duty trucks. Heavy duty trucks like semis have similar issues when not classified as an RV.

Let us also define light truck: Despite the "Heavy Duty" and "Super Duty" labels found on the skin of beefier trucks, anything classified as a one ton or less is considered a light truck by the RV, trucking, and insurance industries.

Purchase Price

It will tow anything on the lot!

My wife and I visited several RV dealers in Texas when shopping for a fifth wheel. We usually drove our car so the dealer would not see our F-550 truck. One of my favorite questions to ask after seeing the trailer weight was "So, how big a truck do I need to tow it?" Out of all salespersons I dealt with, only one gave an honest answer when he suggested that I check with the truck manufacturer for the proper ratings. All trailers we were considering weighed at least 15,000 lbs, and usually more. Despite the fact that in 2004 there were no stock one ton trucks rated to tow that much weight, the one ton was the largest truck any salesman recommended.

One time we were driving our truck and found an RV dealer we wanted to visit. I asked the salesperson the same question about truck size, but having seen our F-550, he assured us that it was sufficient. As we sat there looking at brochures, the manager came by and we engaged in a friendly conversation. I told them I appreciated their "honesty" about the size of truck I need, and asked why so many of the other dealers told me a one ton is enough. He said that telling a Texan his truck can't town something is like calling his baby ugly. In other words, they will tell an unsuspecting RV buyer whatever they think will make the sale, even if that means their customer will get on the road in unsafe conditions.

The purchase price of a large truck may be a stumbling block for many. If you already own a pickup truck and plan to tow with it, please make sure you understand the factory ratings of that truck before you go shopping for an RV. Knowing the limits of your truck is crucial to keep you in line with what you can and cannot tow. Knowing before shopping is important because most dealers will tell you that "your truck will tow anything on the lot", or a variation thereof. This happens so often that you can almost consider it a universal response. I believe the primary reason for this answer is cost—if a salesperson can convince you that your current truck, or a less expensive light truck is all you need, then it will be easier for you to afford his RV.

Whether buying a new or used truck, consider all of the following:

  • How large a truck is required to safely tow the RV? How much does this truck cost?
  • If you already have a truck, how much will it cost to fit it for towing? Consider things like hitch installation, upgrading suspension, installing "heavy duty tow package" offered by most manufacturers.
  • If buying a new truck, how much extra will it cost to fit it for towing? Consider things like bed installation on chassis, hitch installation, upgrading suspension, installing "heavy duty tow package" offered by most manufacturers.
  • Will any of the modifications required for towing jeopardize the truck warranty?

If the price of a large truck is too high, the only safe way to avoid it is to select a lighter trailer, which in turn requires a lighter, less expensive truck.


For trucks over one ton, finding personal auto insurance may be a challenge. Many insurance companies will not insure anything above a light truck, and others may only insure medium duty trucks as a commercial vehicle at the commercial rate.

My advice is that you contact an insurance agent or request quotes from online sources (see list below), after you know the type of truck you need, but before buying the RV.

Here is my personal experience with finding insurance for my Ford F-550, a medium duty truck: After trying several online insurance quoting services and realizing that the largest Ford truck I could select was an F-350, I knew that insurance shopping would be a challenge. Having no success with the online quotes, I called a few insurance companies, even some that specialize in RV insurance, and without exception they referred me to their commercial division. I was not interested in paying the higher commercial rate, so I called my insurance agent.

After searching for several days, my agent informed me that Travelers may be willing to insure the F-550, but had some questions. They distinguish between private and commercial vehicles by weight; anything 10,000 lbs and over was considered commercial. I spoke with the Travelers representative on the phone and she asked me how much the truck weighed. I told her it weighs just under 9,000 lbs. A few days later I received a call saying that they can only insure the truck as commercial. "The other rep said that private insurance applies under 10,000 lbs," I complained. The new rep confirmed that this was true and told me that the Ford dealer they contacted said the truck weighed 15,000 lbs. I tried to explain that the truck's GVWR, or the maximum it could weigh was 15, but the actual weight was 9. The rep took this information and tried confirming again. This went back and forth a few times until I offered to weigh the truck and bring in the certified weight slip. This would have been sufficient for the insurance company, but they preferred something official from Ford. About that time I found among the truck papers the factory "shipping weight" of 7,600 lbs. I assume this is how much the dry truck chassis weighed when it left the factory. Once I faxed this document over to Travelers, it finally settled the issue and they agreed to insure the truck as a personal vehicle.

My experience illustrates how you may need to do a bit of legwork to find appropriate insurance for an MDT. It also illustrates that insurance agents and truck dealers may not understand the different weights associated with a vehicle.

To expedite the insurance process, do the following for medium and heavy duty trucks:

  • Avoid an unpleasant surprise by getting an insurance quote before buying the truck or the RV.
  • Have the shipping weight from the truck documentation available.
  • If shipping weight is not available, weigh the truck and have the official weight slip available.

Places to request insurance quotes:

  • If you already have a good relationship with an insurance agent, tell them what you need and let them do all the legwork.
  • For medium duty trucks, request a quotation online at one of these companies. These web sites allow free-form entry of vehicle model or list some MDT truck models, so you are not limited to light trucks.
  • For light trucks, request a quotation online at one of these companies:

See also the RV Insurance FAQ's.

Licensing Requirements

Review the RV Driver's License Requirements page and contact your state to confirm if you require a special license or an endorsement to tow your recreational vehicle. Determination for special licensing is usually based on the GVWR or the GCWR, so be sure you understand what those numbers are for your truck and RV (see Understanding RV Weights).

If you are told that you need a CDL, do further investigation because this should not be the case, unless you are truly driving a commercial vehicle. Most RV's can be driven with a passenger car operator's license, but large RV's may require a higher class license.

Fuel Consumption

The laws of physics play a significant role in how much you will be spending on fuel. Larger trucks and trailers have more mass and require more energy to move.

Trucks configured for towing large trailers are equipped with rear differential ratios of 4.10 to 4.88, and even lower (larger number is a lower ratio). Low rear end ratios mean more fuel consumption, towing or not.

For diesel trucks you can expect fuel consumption between 8 and 15 mpg while towing, depending on numerous factors such as total weight, rear differential ratio, wind resistance against frontal area, topography, engine performance enhancements, etc. Consumption will be slightly higher for gasoline engines. When driving the truck without the trailer, your fuel consumption should improve roughly 2 to 4 mpg.

Suggestions for improving fuel consumption:

  • Go easy on the accelerator. There is a definite improvement if you can keep your speed at 55 mph or less, and by not accelerating aggressively.
  • Maintain tire inflation at the proper pressure.
  • Research engine performance enhancement products such as larger air intakes, more efficient air filters, and engine tuners or "chips". I use the Superchips tuner in my F-550 while not towing—this improves fuel economy by 2 to 3 mpg.

    WARNING: Adding any performance products to your truck may void the warranty and damage truck components, if installed improperly. Yes, there is a law that states a manufacturer cannot automatically void the warranty just because an aftermarket product was added, but do you really want to fight that battle?

    WARNING: Installing an engine tuner will provide more horsepower. If you are towing near the GCWR of the truck, the additional horsepower may overheat the engine and overload the drive train. Under these conditions, overheating will occur much quicker on hills and can cause damage if not monitored closely. An overloaded drive train means shortened transmission life.

Maneuverability & Storage

If you like to wait in parking lots until a space opens near the store entrance, a large truck may not be for you. Larger the truck, the farther you will have to park from buildings. It is not unusual having to find a neighboring parking lot with more space because the establishment I'm visiting has very small parking spaces. At first a large truck may be intimidating to drive, but anyone possessing good driving skills and common sense should get a hang of it quickly. My wife and I drive our F-550 on the highways and in town, and neither one of us feel intimidated in most conditions. An occasional tight spot may get us flustered, but so far it all has been manageable.

Consider the following issues related to maneuverability and storage, before buying a large truck, especially a dually:

  • Will it fit in the driveway?
  • If it won't fit in driveway, can it be parked near the house?
  • Is access to driveway or back of house so tight that turns may be difficult?
  • Driving a wide truck on narrow roads will be more stressful. Some drive-up windows cannot accommodate wide trucks.
  • Driving a truck with long wheelbase requires wide turns.
  • Parking at stores and malls will require more time and more walking; be prepared to look for alternate parking nearby.
  • Judging distance in front and right side of large trucks is more difficult; in tight spots you may need help from others, or you may need to hop out occasionally to check clearance.

If you are facing some of the issues presented above, you should never overcome them by downsizing to an inadequate and underrated tow vehicle. By doing so, you may save yourself some aggravation and cost up-front in exchange for nerve-wracking trips and sacrificed safety.